Sharon: Rates of temperature change in the future can only "accelerate" due to a few things. One is an increase in emissions. But climate modelers can't predict future emissions. A second is a change in the fraction of emissions that remains in the atmosphere which the IPCC says has been 56% for decades. The third is a change in the temp…
Sharon: Rates of temperature change in the future can only "accelerate" due to a few things. One is an increase in emissions. But climate modelers can't predict future emissions. A second is a change in the fraction of emissions that remains in the atmosphere which the IPCC says has been 56% for decades. The third is a change in the temperature gain per Gt of emissions. But the IPCC uses the same conversion from Gt CO2 to delta-T out to 2100 so that won't change according to their own models. Hence, the only acceleration of delta-T that is possible would be due to an increase in emissions and all the current data points in the opposite direction. Conclusion: delta-T aint gonna accelerate.
Thanks, Donald! I guess there might be some argument that there might be an increase in emissions (Chinese coal plants, who knows?). I guess my point is whether increases in temp are linear with regard to emissions or some other function. So take the trends from fossil fuels graph from EPA here https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data.. would the ave temp have gone up linearly or some other function? I think we could tell this from observed data. Maybe more years of 56% remaining in the atmosphere adds up to more total in the atmosphere? Sorry if these are dumb questions.. I'm a biologist.
Sharon: I think the point is that the rate of temperature gain doesn't willy nilly decide to go up or down on its own. If it were 100% determined by CO2 emissions (which from year to year it isn't) then it could only go up if emissions per year increased, the fraction remaining in the atmosphere increased, or the algorithm converting Gt CO2 to temperature gain changed. The IPCC uses the same algorithm from 2015 to 2100. The fraction remaining in the atmosphere (according to IPCC) hasn't changed in 40 years. Ergo, the whole business of scenarios has no science in it at all and it all comes down to future CO2 emissions which nobody can predict.
Sharon: Rates of temperature change in the future can only "accelerate" due to a few things. One is an increase in emissions. But climate modelers can't predict future emissions. A second is a change in the fraction of emissions that remains in the atmosphere which the IPCC says has been 56% for decades. The third is a change in the temperature gain per Gt of emissions. But the IPCC uses the same conversion from Gt CO2 to delta-T out to 2100 so that won't change according to their own models. Hence, the only acceleration of delta-T that is possible would be due to an increase in emissions and all the current data points in the opposite direction. Conclusion: delta-T aint gonna accelerate.
Thanks, Donald! I guess there might be some argument that there might be an increase in emissions (Chinese coal plants, who knows?). I guess my point is whether increases in temp are linear with regard to emissions or some other function. So take the trends from fossil fuels graph from EPA here https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data.. would the ave temp have gone up linearly or some other function? I think we could tell this from observed data. Maybe more years of 56% remaining in the atmosphere adds up to more total in the atmosphere? Sorry if these are dumb questions.. I'm a biologist.
Sharon: I think the point is that the rate of temperature gain doesn't willy nilly decide to go up or down on its own. If it were 100% determined by CO2 emissions (which from year to year it isn't) then it could only go up if emissions per year increased, the fraction remaining in the atmosphere increased, or the algorithm converting Gt CO2 to temperature gain changed. The IPCC uses the same algorithm from 2015 to 2100. The fraction remaining in the atmosphere (according to IPCC) hasn't changed in 40 years. Ergo, the whole business of scenarios has no science in it at all and it all comes down to future CO2 emissions which nobody can predict.